Pump



Aprfl l, 1941. J. P. DAMONTE PUMP Filed April 22, 1939 2 Sheets-Sheet 1April 1, 1941. 9 J. RDAMONTE 2,236,706

PUIEP Filed April 22, 1939 2 Sheets-$11961. 2

Patented Apr. 1, 1941 UNITED STATE-S PATENT OFFICE PUMP John P. Damonte,New Orleans, La.

Application April 22, 1939, Serial No. 269,536

4 Claims.

This invention relates to improvements in Dumps, particularly in thetype sometimes known as a turbine pump. This particular pump is devisedto meet rather widely varied conditions; in other words it is adapted topump fluids of a gaseous nature and liquids which may or may not beclear of solid matter.

The pump is particularly advantageous when used under the lastcondition, mainly because of its having fairly widely spaced bladeswhich together with the internal construction avoid the formation ofclose comers as well as pockets in which solid matter can lodge in theevent that liquid is pumped having an accumulation of such mattertherein. Regardless of the character of fluids to which the pump isadapted, it is the novel formation of the blades which is relied uponfor an eflicient performance. With this premise in mind the objects ofthe invention are as follows:

First, to provide a pump for fluids, either gaseous or liquid, anoutstanding characteristic of which is the continuously varied pitch ofthe blades, the involutecurve upon which each blade is constructedhaving the advantages of impelling the fluid with centrifugal force uponinitial contact at the suction end so as to insure a copious influx ofthe fluid, then later acting on said fluid with a screw principle to addpressure thereto and thus to expel the fluid with considerable force.

Second, to provide a pump of the foregoing character wherein thedischarge opening is located on the end of the casing, as distinguishedfrom its customary location on the periphery of the casing, thisarrangement being especially suited to the trailing edges of the blades.

Third, to provide a pump wherein each blade is the composite of aninvolute curve and a twist which develops at the leading edge andterminates at the trailing edge, the extent of the twist beingsubstantially 90 so that the trailing edge stands ,at- -approximately 90from the leading edgein itsangular position, and spaced away from theleading edge the axial distance of the hemi-spherical rotor head ofwhich it is a part.

Fourth, to provide a pump wherein the foregoing blade structure beginswith a coarse pitch at its leading edge, enabling the utilization of theprinciple of centrifugal force, and ends with a fine pitch at itstrailing edge, enabling the utilization of the screw principle.

Fifth, to provide a pump blade of the foregoing kind wherein thepressure face is either smooth, as is suitable for ordinary pumping, oris stepped particularly illustrating the improved rotor construction,

Figure 2 is an end view of the pump illustrating the novel arrangementof the discharge conduit,

Figure 3 is a front elevation of the rotor,

Figure 4 is a rear elevation of the rotor,

Figure 5 is a diagrammatic plan view of one of the blades, particularlyillustrating the substantially angular relationship between the leadingand trailing edges,

Figure 6 is an elevation of the inside of the foundation plate,illustrating the reverse side of the discharge'conduit in Fig. 2,

Figure 7 is an elevation of the inside of the outer shell,

Figure 8 is a detail perspective view of one of the blades, particularlyillustrating the edge insert,

Figure 9 is a cross section taken on the line 9-9 of Figure 8,

Figure 10 is a perspective view of a modified form of blade, wherein thepressure face is stepped, and

Figure 11 is a detail sectional view of a portion of the stator whereinthe interior is lined with corrugated flexible material.

The pump is generally designated l, the outer shell 2 and foundationplate 3 of which constitute what is herein known as the stator orcasing. The stator is mounted rigidly in any desired way, the particularmode of mounting being immaterial. One type of mount comprises a bracket4 (Fig. 2) which in practice will have holes through which bolts can bedriven into an adjacent solid support. This bracket includes anextension 5 which is secured between the flanges 6 and I respectively ofthe outer shell 2 and of the inlet pipe 8.

.,The direction to which the inlet pipe 8 extends off from the pump isalso immaterial. If the bracket 4 were bolted down to a horizontalsupport, the inlet pipe 8 would extend off in a more orless horizontaldirection to. the source of fluid. The previously mentioned flange 6comprises a part of a. passage 9 which is formed on the outside of theshell 2. The inner end of this passage terminates in a fluid inlet I0.This inlet is located axially of the pump. In other words, it iscentered both in respect to the stator and the rotor.

Said rotor comprises a shaft II which carries a hemispherical head i2.The crown l3 comprises a rounded dome, and obviously so because of thehemispherical nature of the head. This dome confronts the fluid inlet IDas plainly shown in Fig. 1, the free edge l4 confronting the previouslymentioned foundation plate 3. The head l2 can be made a part of theshaft l I in any one of a variety of ways. Usually it is not practicableto make the two parts integral, the preferred mode of manufactured beingto provide the shaft with a flange 15 which is screwed at I6 into thehub H of the head I2.

The end l8 of the shaft (Fig. 1) is supported by a bearing l9 whichoccupies a recess in the wall of the passage 9. The opposite end of theshaft is adapted to be driven by a motor of any conventional type. Theouter shell 2 and the foundation plate 3 are flanged at 2|, 22, theseflanges being in the nature of outstanding ears (Figs. 7 and 6) whichhave holes for securing bolts.

A fairly heavy bearing 23 (Fig. 1) completes the support of the shaft H.lubricated in any known way, for example, by means of the grease nipple24. A discharge conduit 25 is made integral with the foundation plate 3(Fig. 1). This conduit comprises part of the fluid outlet 26 (Fig. 6)which is almost three-fourths of a circle in extent.

It is noted in Fig. 1 that the discharge conduit 25 lies against or isan integral part of the end of the foundation plate 3. This is incontradistinction to the prevailing disposition of the discharge conduiton the periphery of the pump casing. The fluid outlet 25 and the conduit25 are, virtually, the same part because of their being in directconnection. The conduit 25 is helical in nature, that is to say, if itwere continued (Fig. 2) it would define a helix. This formation of theconduit causes the fluid outlet 26 to have a progressively increasinginternal size.

This is readily observed in Fig. 1 wherein the outlet 26 is fairlyshallow at the right and much deeper at the left. Although said outletis of the progressively increasing size mentioned, it is, nevertheless,located solely in the plane of the plate 3. This is in strict accordancewith the location of the conduit 25 on the end of the casing.

Particular attention is directed to the formation of the rotor blades.Inasmuch as these are all alike, the description of one will suifice forall. The blade 21 (Fig. 8) has an involute curvature. When viewing thisblade from its leading edge 28 to its trailing edge 29 (Fig. 3), it isseen that the curvature is generated on a spiral order. But thiscurvature is not the generation of a given point in a common planebecause it is obviously necessary to make the blade so that it will fltthe rounded dome l3.

This makes it necessary to give the blade a twist on a spiral order sothat it will fit the foregoing contour of the head. The extent of thistwist is well shown in Figs. 1 and 5. These views illustrate the spacingof the trailing edge 23 from the leading edge 23 as amounting to theaxial dimension of the head 42. In other words, the

This bearing isv blade 21 starts with its leading edge 28 at the crownof the dome i3 and ends with its trailing edge flush with the free edgeI4 0! the head I2.

Thus the blade 21 has a composite involute curvature and twist. Besidesproviding a flt of the blade on the rounded dome of the head l2, thisblade structure disposes the leading and trail ing edges atsubstantially right angles to each other. The leading edge 28 coincidesapproximately with the fluid inlet (0 and is substantially parallelthereto. Said leading edge is also substantially parallel to the axis ofthe rotor. The advantage of this arrangement is that the leading portionof the blade exercises a definite centrifugal action on the fluid as thelatter is drawn in at the inlet l0..

This centrifugal action drives the fluid back into the shell 2'towardthe outlet 26, into which outlet the fluid is driven with considerableforce due to the fact that the trailing portion of the blade is resolvedinto what closely resembles a screw pitch. This is readily seen in Fig.l; the,

leading portion of the blade defines a very course pitch, driving thefluid with a centrifugal action, whereas the trailing portion of theblade defines a fine pitch, completing the driving of the fluid with ascrew action.

Referring now to the collective blades (Fig. 3) it will be noted thatthe spacing 30 between the blades is fairly wide. The fluid is conductedthrough the pump on an internally streamlined order. The channel 3i(Fig. 1) comprising the distance between the confronting surfaces of thehead l2 and shell 2 is equal in depth to the radial dimensions of theblades. The ample internal spacings thus afforded permit the use of thepump on liquids which are loaded with more or less solid matter, thevirtual absence of sharp ends preventing the likelihood of internalclogging.

Attention is directed to Figs. 8 and 9. The rim of the blade 21 israbbeted at 32 for the occupancy of an insert 33. The inside of therabbet is desirably undercut. The insert may comprise any desiredmaterial, for example, a rubber strip. Regardless of the nature of theinsert, the rabbet 32 is supplemented by a retainer 34 which is securedat 35 in a channel 36 on one side of the blade 21. This retainer hasgripping means 31 which bites into the insert and coacts with theundercut in securely holding the insert in the rim of the blade.

The obvious purpose of the insert is to secure a tight engagement of theblade with the interior of the shell 2. While the insert 33 is intendedto be used in most instances yet it is conceivable that the rim of theblade can be machined so :arefully as to secure a tight working fitagainst the shell without an insert,

The convex side of the blade comprises the pressure face. It is thisface which actually drives against the fluid in expelling it from thechannel 3| into the outlet 26. In most instances the pressure face issmooth (Figs. 5 and 8) but in some instances an improved effect isderived from the arrangement in Fig. 10. Here the blade 210. has thepreviously mentioned pressure face 38 arranged in a series of steps 39.These steps define an equal series of vacuum pockets 40. These pockets,as their name implies, have a tendency to produce a partial vacuum asthe blade sweeps across the channel 3|. The use of the steps 35 is ofparticular advantage in the larger sizes of pumps wherein the creationof a greater suction is desirable.

In Fig. 11 the pump shell is designated 21). The internal surface 4| islined with a corrugated flexible material 42. Usually this material willcomprise rubber, but it may comprise some other flexible substance. Whenthe blades pass over the lining 42 they cause a compression of thecorrugations of the surface and cause a positive displacement effect.This, in turn, creates a partial vacuum and adds considerably to theefliciency of the pump.

It has been found in practice that the advantage of having the bladetraverse the corrugated surface as in Fig. 11, is that the expansion andcontraction of the inward crests of the corrugations caused by thepassage of the blades causes a very definite displacement eifect whichis more pronounced than in the instance wherein the blades traverse asmooth surface. The definitely constituted suction or vacuum derivedfrom said increased displacement results in an increase in emciency ofthe Pump.

It is believed unnecessary to amplify the description with a statementof the operation of the pump, other than to say that when the rotor isdriven in the proper direction (Fig. 3) a suction will be set up at theinlet l0, drawing in the fluid for displacement into the outlet 26. Thepump is well adapted as a supercharger for internal combustion enginesor as an air pump for ventilating and air conditioning systems. But whenpumping air instead of liquids it would not be 2. A pump comprising astator having an outer shell of internal hemi-spherical shape, saidshell having an inlet in the axial center of the hemisphere, and afoundation plate, carrying said outer shell and having a fluid outletlocated solely in the plane of said plate and in perpendicularity to thestator axis, a rotor revolubly supported by the stator, having ahemi-spherical head matching and confronting the hemi-spheric shape ofthe shell and at least one blade carried by the rotor having a leadingedge substantially parallel to the stator and rotor axes, said bladehaving an involute curvature and developing spirally to flt thehemi-spherical contour of said head, said blade also having a continuoustwist adapting it to said head and terminating in a trailing edgestanding at substantially in angular position from the leading edge.

3. In a pump, a hemispherical shell having a fluid inlet, a revolublerotor having a hemispherical head spaced from and matching the shell, ablade on the head being of involute curvature and of spiral shape toconform to the spherical form of the head, said blade having leading andtrailing edges standing substantially at right angles to each other,said blade having a pressure face provided with a succession of stepsdefining a series of vacuum pockets.

4. In a. pump, a stator shell, a rotor revoluble in respect to saidshell and having a blade, the' rim and an adjacentside oi the bladehaving a rabbet and a channel respectively, an insert fitted in saidrabbet to bear against the interior of the shell, and retainer meanssecured in the channel having gripping means biting into the material ofthe insert to hold the insert in place.

JOHN P. DAMONTE.

